HeightFieldNext8 Class Reference

This class implements the structure coding the flow direction over a terrain. More...

#include <heightfield.h>

Inheritance diagram for HeightFieldNext8:

Public Member Functions
	HeightFieldNext8 (const HeightField &, bool)
	Create the flow direction field.
	HeightFieldNext8 ()
	Empty.
	~HeightFieldNext8 ()
	Empty.
unsigned char	At (int, int) const
	Return the flowing directions, compacted into one byte.
unsigned char	At (const QPoint &) const
	Return the flowing directions, compacted into one byte.
QPoint	FlowTo (const QPoint &) const
	Return the steepest flow direction.
QPoint	FlowTo (const QPoint &, int) const
	Return the k-th flow direction.
int	N (int, int) const
	Return the number of flowing directions.
int	N (const QPoint &) const
	Return the number of flowing directions.

Protected Member Functions
unsigned char	Flow (const HeightField &, const QPoint &, bool) const
	Compute the flow directions at a given point.

Protected Attributes
QVector< unsigned char >	flow
	Array of directions.

Detailed Description

This class implements the structure coding the flow direction over a terrain.

Constructor & Destructor Documentation

HeightFieldNext8()

HeightFieldNext8::HeightFieldNext8	(	const HeightField &	h,
		bool	steep )

Create the flow direction field.

Parameters

h	Heightfield.
steep	Set to true if steepest slope is needed (which is the D8 algorithm), false for complete flow (which is D∞ algorithm).

Member Function Documentation

At() [1/2]

unsigned char HeightFieldNext8::At ( const QPoint & p ) const

inline

Return the flowing directions, compacted into one byte.

Parameters

p

Point.

At() [2/2]

unsigned char HeightFieldNext8::At ( int i, int j ) const

inline

Return the flowing directions, compacted into one byte.

Parameters

i,j	Integer coordinates of the sample.

Flow()

unsigned char HeightFieldNext8::Flow ( const HeightField & h, const QPoint & a, bool steep ) const

protected

Compute the flow directions at a given point.

Parameters

h	Heightfield.
a	Point.
steep	Boolean, set to true to compute only the steepest slope, false to compute the average flow.

FlowTo() [1/2]

QPoint HeightFieldNext8::FlowTo

(

const QPoint &

p

)

const

Return the steepest flow direction.

Note that the instance should have been initialized with the steepest slope algorithm. This is the same as:

HeightFieldNext8 flow;
QPoint p;
QPoint f=flow.FlowTo(p,0);

Parameters

p

Point.

FlowTo() [2/2]

QPoint HeightFieldNext8::FlowTo	(	const QPoint &	p,
		int	k ) const

Return the k-th flow direction.

Note that the instance should have been initialized with the average flow algorithm.

Parameters

p	Point.
k	Index of the k-th flow direction.

N() [1/2]

int HeightFieldNext8::N

(

const QPoint &

p

)

const

Return the number of flowing directions.

Parameters

p

Point.

N() [2/2]

int HeightFieldNext8::N	(	int	i,
		int	j ) const

Return the number of flowing directions.

Parameters

i,j	Integer coordinates of the sample.